1. Technical Field
The present invention relates to a flow-path member, a liquid ejecting head, and a liquid ejecting apparatus and, particularly, relates to a flow-path member in which ink flows as a liquid, an ink jet type recording head which ejects ink supplied from the flow-path member, and an ink jet type recording apparatus.
2. Related Art
An ink jet type recording head which includes a head main body in which a pressure generation chamber communicating with a nozzle opening through which ink droplets are discharged is deformed by a pressure generation unit, such as a piezoelectric element, in such a manner that an ink droplet is discharged through the nozzle opening and a flow-path member which constitutes a flow path of ink supplied to the head main body is known as a liquid ejecting head.
A common manifold relating to respective pressure generation chambers is formed in the head main body. The manifold receives ink from the flow-path member and distributes the ink among the respective pressure generation chambers. Connection flow paths connecting the respective pressure generation chambers and the manifold are provided in the head main body. The connection flow paths communicate with the manifold, in a state where a flowing direction of ink in the connection flow path and a flowing direction of ink in the manifold have the same direction component. Accordingly, it is possible to allow ink to flow from the manifold to the connection flow paths while preventing the flow velocity of the ink from being extremely reduced. As a result, air bubbles are prevented from remaining in the connection flow paths, which result from a reduced flow velocity in the ink (see JP-A-2003-320664, for example).
However, in the case of the above-described configuration in which the flow velocity of ink is prevented from being reduced, the shapes or the arrangements of the manifold and the connection flow paths are limited. As a result, the degree of freedom in the configuration of a flow path, such as the manifold and the connection flow path, is reduced. Meanwhile, it is conceivable that the connection flow path and the manifold communicate with each other in a state where the flowing direction of ink in the connection flow path and the flowing direction of ink in the manifold have opposite direction components, in such a manner that the degree of freedom in the configuration of the flow path is ensured. However, in this configuration, there is a concern that the velocity of ink flowing from the manifold to the connection flow path may be reduced, and thus air bubbles may remain in the connection flow path.
Such a problem is not limited to the connection flow path which connects the manifold and the respective pressure generation chambers, in the head main body. The problem is shared by a flow-path member which has a flow path portion as a main flow path and a plurality of bifurcation flow path portions communicating with the flow path portion and in which ink is supplied from the flow path portion to a head main body through the bifurcation flow path portions, by connecting the bifurcation flow path portion and the head main body.
In other words, in the flow-path member having a configuration in which the flow path portion and the bifurcation flow path portions communicate with each other in a state where the flowing direction of ink in the bifurcation flow path portion and the flowing direction of ink in the flow path portion have the same direction component, it is possible to allow the ink to flow from the flow path portion to the bifurcation flow path portion while preventing the flow velocity of the ink from being extremely reduced. However, the arrangement of the bifurcation flow path portions and the flow path portion is limited, and thus the arrangement of the head main body is limited.
In contrast, in a flow-path member having a configuration in which a flow path portion and a bifurcation flow path portion communicate with each other in a state where the flowing direction of ink in the bifurcation flow path portion and the flowing direction of ink in the flow path portion have opposite direction components, it is possible to ensure a high degree of freedom in the configuration of the flow paths. However, there is a concern that the velocity of ink flowing from the flow path portion to the bifurcation flow path portion may be reduced, and thus air bubbles may remain in the bifurcation flow path portion.
Such a problem is not limited to a flow-path member which supplies ink to a head main body or an ink jet type recording head which discharges ink. The problem is shared by a flow-path member which supplies, to a head main body, liquid other than ink, a liquid ejecting head, and a liquid ejecting head which eject liquid.